Southern California Gas officials say a seventh effort to shut down an out-of-control well venting methane from a natural gas storage field north of Los Angeles has failed.
Well-control experts once again tried to force mud and brine down the damaged well over the Christmas holiday, trying to stem a gusher of 67,000 pounds per hour of methane. It’s considered the worst release of climate-changing methane from the oil and gas industry in California history.
But the company officials said Monday the effort to quash the flow couldn’t overcome the upward pressure of the gas.
Even so, there was some positive news. Crews succeeded in locating the underground path of the damaged well pipe. That is a crucial step, because Southern California Gas is drilling a relief well, and now that well can find its mark.
The experts in the recent failed effort to stanch the well include those with Boots & Coots Services, a division of Halliburton that advertises its ability to “address the industry’s most challenging well control problems,” and offers the telephone number 1-800-BLOWOUT.
Southern California Gas, which is part of San Diego-based Sempra Energy, lost control of the well on Oct. 23. The well had been used to inject gas underground for storage since 1973. Since the rupture, it has released approximately 145 million pounds of methane, according to the most recent estimates from the California Air Resources Board. For perspective, industrial plant inspectors who scan for methane leaks hustle to eliminate escapes of even one pound per day of the gas.
The Dec. 23 estimate from the air board is based on measurements taken by Scientific Aviation, which has made six flights through the gas plume so far and will soon make another.
The well is one of 115 in the Aliso Canyon natural gas storage field, some 25 miles north of Los Angeles and just over the hills from the San Fernando Valley communities of Porter Ranch, Chatsworth and Granada Hills.
The rate of release has surprised methane experts for its ferocity and because California is under a legal mandate to reduce carbon emissions to flatten the trajectory of climate change. Methane is especially concerning because it has a marked ability to trap heat in the atmosphere, thanks to the nature of its carbon-hydrogen bond. Its formula is CH4.
About the leaking well officials know this much: Its 7-inch steel wall, or casing, is ruptured at approximately 480 feet. From there, gas is migrating downward to a depth of about 1,000 feet, then slipping past the bottom end of the 11-inch outer casing and up out of the ground, said Jason Marshall, chief deputy director of the California Department of Conservation.
The pressure of the escaping gas has blown away earth in an area “about the size of two, three, four parking spaces,” Marshall said. The well and its concrete pad are located on a ridgeline.
This latest failure to control the well from above means the gas utility will continue with the solution it has pursued since Dec. 4 — drilling a relief well that will intercept the damaged one. That intersection will happen at a depth of approximately 8,500 feet. The relief well bore has reached a depth of about 3,800 feet, said Melissa Bailey of Southern California Gas. With that progress and now with the pinpoint location of the pipe underground, the company has shortened the estimate for completion to late February.
The social cost of the release has been high. More than 2,000 families have moved away from Porter Ranch, parts of which lie less than a mile south of the storage field, tired of smelling gas and suffering its negative effects. Hundreds more have been trying to get out, but the exodus has dried up the supply of comparable homes. The gas company has been ordered by the Los Angeles city attorney to find housing faster.
Southern California Gas and its parent company Sempra also have been named in several lawsuits and must pay for the relocations.
